vb绘图

2-4：Imports System.Math

Public Class Form1

Private Sub Draw_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Draw.Click

Dim g As Graphics

Dim p As Pen

Dim i, j, oldx, oldy As Integer

Dim r As Integer = 120

Dim pi As Single = 3.14159

Dim px(0 To 4) As Integer, py(0 To 4) As Integer

g = PictureBox1.CreateGraphics

g.SmoothingMode = Drawing2D.SmoothingMode.AntiAlias

p = New Pen(Color.Black)

'设定坐标系

g.TranslateTransform(160, 120)

g.ScaleTransform(0.6, -0.6) '坐标缩小并Y轴朝上 g.DrawEllipse(p, -1 * r, -1 * r, 2 * r, 2 * r)

'计算五边形顶点

For i = 0 To 4

px(i) = r * Cos(0.1 * pi + 0.4 * pi * i)

py(i) = r * Sin(0.1 * pi + 0.4 * pi * i)

Next

oldx = py(0) : oldy = py(0)

For i = 0 To 4

For j = 0 To 4

If i <> j Then

g.DrawLine(Pens.Black, px(i), py(i), px(j), py(j)) End If

Next j

Next i

倾斜矩形：Private Sub Rect_Angle(ByRef x As Object, ByRef y As Object, ByRef W As Object, ByRef H As Object, ByRef th As Object)

'x, y为旋转基点，th为倾角，W,H为矩形的长、宽

Dim x1, y1, x2, y2, x3, y3, x4, y4 As Integer '矩形的四个角点 th = th * pi / 180

x1 = x

y1 = y

x2 = Int(x1 + W * Cos(th))

y2 = Int(y1 - w * Sin(th))

x3 = Int(x2 - h * Sin(th))

y3 = Int(y2 - h * Cos(th))

x4 = Int(x3 - w * Cos(th))